KR0142610B1 - Nulti-layer structure making method by semisphere type head dom of hot forging - Google Patents

Abstract

The present invention relates to a method for manufacturing a multilayer structure using a method of manufacturing a hemispherical head help structure by a hot forming method to simultaneously produce a multi-layered HEAD DOME structure. It provides cost reduction and time efficiency by providing a multi-layer structure manufacturing method using a hemispherical head-help structure manufacturing method by a hot forming method that can be manufactured at the same time, therefore large generators such as nuclear pressure vessel, petrochemical pressure vessel and It can be usefully used for manufacturing industrial equipment.

Description

Manufacturing method of multi-layer structure using hemispherical head-support structure manufacturing method by hot forming method

(A) to (b) of Figure 1 is a flow chart of the method of manufacturing a hemispherical head help structure by the conventional hot forming method,

2 (a) to 2 (b) are flowcharts illustrating a method for manufacturing a multilayer structure using the method for manufacturing a hemispherical head help structure according to the hot forming method of the present invention.

* Explanation of symbols for main parts of the drawings

1 ': Ingot 1: Disc

1-1: 1st disc 1-2: 2nd disc

2; lower upper width and longer mold 3: lower rotation round mold

4: upper head help shape forming mold 5: lower head help shape forming mold

6: supporter

The present invention relates to a method of manufacturing a hemispherical head help structure (HEAD DOME) structure by the hot forming method, in particular a method of manufacturing a multi-layer structure using a hemispherical hemispherical head help structure manufacturing method by a hot forming method to be able to manufacture a multi-layer head help structure at the same time It is about.

The method of manufacturing a hemispherical head help structure by the conventional hot forming method is to increase the disc by a special disc stretching forging method and then to form a large hemispherical head help structure to obtain a product of accurate dimensions and shapes; First, the ingot is stretched, cut, pressed and stretched into a disc shape to a certain size, and then processed and molded into a hemispherical head-assist shape in an open state (pressing work in a molding machine).

Such a conventional technique is well shown in the method of manufacturing a hemispherical head help structure by hot forming method, filed No. 93-3962, filed by Korea Heavy Industries Co., Ltd. on March 16, 1993. If this is shown in order, as shown in FIG.

(A) of FIG. 1 is a cross-sectional view showing that pressing and cutting is performed after drawing the ingot 1 ', which is a material, and (b) of FIG. The upper section is a cross-sectional view sequentially showing that the diameter of the disc 1 is increased in an arbitrary direction while the thickness is reduced by using the mold 3 with the narrow width and the long length. (C) of FIG. 1 is a cross-sectional view sequentially showing a process of forming a hemispherical help shape by processing a material having a diameter increased with the disc 1, and (d) of FIG. 1 shows a shape of a head help after completion of molding. It is a cross section.

Operations and effects of the cited patents performed in the above order are well known and thus will not be described.

Such a prior art manufacturing method has an uneconomical disadvantage, such as not only the operation rate of the heating furnace is lowered by heating the disc one by one when heating, but also the operation rate of the molding machine is reduced by molding the heated disc one by one.

In addition, when hot forming a large head help structure, by forming a single layer disc, it is necessary to separately manufacture the upper head help shape molding die and the lower head help shape molding die for molding according to the head help dimensions. Therefore, as the cost of manufacturing the mold increases, head-help manufacturing cost increases, and furthermore, since the mold manufacturing period is required, there is a difficulty influencing the product manufacturing process period.

The present invention is to solve the problems of the prior art as described above, multi-layer structure manufacturing method using a method of manufacturing a hemispherical head help structure by the hot forming method to simultaneously process a multi-layered disc to produce a multi-layered head help structure at the same time. To provide.

That is, in the present invention, a multi-layered disc is loaded into a heating furnace and heated at the same time, and the heated multi-layered discs are simultaneously taken out and placed on the lower head-help molding die and pressed by the upper head-help molding die to simultaneously press several discs. It characterized in that the molding to the shape of the head help.

DETAILED DESCRIPTION Hereinafter, a flowchart of a method of manufacturing a multilayer structure using the method for manufacturing a hemispherical head help structure by the hot forming method of the present invention can be shown as (a) to (b) of FIG. 2. , Which is an embodiment of the present invention.

(A) of FIG. 2 sequentially shows the step (step (c) of FIG. 1) of forming into a hemispherical head-help shape, and the two or more (1 in this embodiment) roughly processed roughly 900 Molding is performed using the upper head help shape molding die 4 and the lower head help shape molding die 5 in the state heated to from 캜 to 950 ° C. As the hemispherical head help structure formed in this process, two or more (two in this embodiment) head help structures 1-1 and 1-2 are formed as shown in FIG.

In the embodiment of the present invention as described above, the first disc 1-1 (which is in contact with the upper end of the lower head help shape molding die 5) and the first disc 1-1 placed on the first disc 1-1 Release material to prevent the two discs (1-1,1-2) from fusion between the two discs (1-2) due to the molding load and friction during hot forming, so that local fusion can occur during molding. The entire surface of the first disc 1-1, and then the second disc 1-2. In other words, a release material must be applied between each of the originals to be laminated when a plurality of originals are laminated.

The release material used here is able to function as a release material even at a molding temperature of 1000 ° C. It should be used to the extent that the original plate 1 is not fused until the final molding is completed, the use of such release material is frictional resistance between the original plate (1) This minimizes the amount of additional head help.

On the other hand, a lubricant (not shown) was applied to the curved portions of the upper head help shape forming die 4 and the lower head help shape forming die 5, which is a disc 1 formed during molding and upper and lower head help. This is to minimize the frictional resistance of the contact surface with the shape-molding molds (4, 5) and to improve the formability.

In addition, immediately after dismantling the formed multi-layered disk 1 from the upper and lower head-shaped molds 4 and 5, the head-support structures 1-1 and 1-2 of the multi-layered state are separated. In the process of shrinking from hot state to cold state, the influence on dimensional change should be minimized.

For reference, the upper head help shape molding die 4 is made of cast steel to withstand high pressure during head help molding, and the curved portion contacted during head help and molding is processed to improve the molding dimension accuracy of the head help. Was carried out. In addition, the lower head help shape forming mold 5 is designed to withstand the load during molding, and is manufactured as a forged steel, and is formed to form a ring shape by forming the upper inside to form a ring (RING) shape. It is more effective in molding and forming a head help shape, and furthermore, an additional effect of minimizing the molding load and improving the formability of the head help at the final stage of molding can be obtained.

Example 1

A head help structure for a nuclear pressure vessel was constructed as follows.

First, a material similar to the material of the product to be molded and reduced to 1/30 of its actual size was tested under the same temperature conditions in a hot state. At this time, the moldability and workability were judged, the function of the release material was checked, and a release material suitable for molding was selected. Part of the release material used here is locally fused during molding, so that the multi-layered head help is not separated from each other until the room temperature cabinet. Therefore, it is important to select a release material that does not have local welding between the original plates 1 after the final molding.

As a result of manufacturing the material of this product of the same size as the actual size based on the above judged and selected data, it was possible to obtain excellent dimensions and formability, and there was no difference in the workability from the molding method by a single layer. It could improve productivity and reduce mold production cost.

In Example 1, the cost of the heating was reduced by heating the head help to be manufactured in multiple layers, and the operation rate of the heating furnace was improved, and the same working conditions, that is, the heating was performed at the same heating temperature. Could get quality.

In addition, in order to manufacture a multi-layered head help structure using a four-head head help shape molding die and a lower head help shape molding die, the heated multi-layer disc in the process of forming a multi-layer heated disc into a head help shape in a molding machine. By simultaneously molding several discs, the operation rate of the molding machine can be improved.

Furthermore, the upper / lower head-help shape molding molds are retained by forming insert discs that can adjust the final dimensions without forming new molds each time according to the head-help dimensions. By using a molding die, it was possible to reduce the cost of manufacturing the head help and to reduce the manufacturing time of the head help according to the mold production.

As described above, the present invention provides a method for manufacturing a multilayer structure using a hemispherical head-help structure manufacturing method by a hot forming method which simultaneously processes a multilayer disc to manufacture a multilayer head help structure, thereby reducing cost and time. Efficiency has been implemented, and thus, it can be usefully used for manufacturing large generators and industrial equipment such as nuclear pressure vessels and petrochemical pressure vessels.

Claims (5)

A first step of stretching the ingot 1 ', cutting it to a predetermined size, and then performing a pressing operation; The forging operation is performed by first extending the disc 1 in an arbitrary diameter direction by the upper upper and lower mold 2 and the lower rotating circular mold 3, and then rotating the rotating circular mold 3 by 90 degrees. A second step; The third step of forming the roughened disc 1 into a hemispherical shape having the desired dimensions and shapes is obtained by using the upper head help shape forming die 4 and the ring-shaped lower head help shape forming die 5. In the method of manufacturing a hemispherical head help structure by a hot forming method which is produced by performing sequentially, a plurality of roughly processed original plates (1) obtained after performing the first and second steps may be formed in the upper head help shape forming die (4) and in the ring shape. Characterized in that the third step of sequentially loading the lower head help shape forming mold (5) and forming a plurality of loaded discs at the same time to produce a multi-layered head help structure (1-1, 1-2) Multi-layer structure manufacturing method using a hemispherical head-help structure manufacturing method by a hot forming method. 2. The hemispherical head according to the hot forming method according to claim 1, wherein each contact surface of the plurality of disks (1) includes a release material to prevent local fusion phenomenon caused by molding load and friction during hot forming. Multi-layered structure manufacturing method using the help structure manufacturing method. The method according to claim 1, wherein the frictional resistance of the contact surface between the upper head help shape forming die 4 and the disc 1 formed on each curved portion of the lower head help shape forming die 5 is minimized, and the moldability is improved. Method for producing a multi-layer structure using a hemispherical head-help structure manufacturing method by a hot forming method characterized in that it comprises a lubricant for. According to claim 1, wherein the molding of the multi-head head help structure (1-1,1-2) is completed in the upper / lower head help shape to minimize the dimensional change occurring in the process of shrinking from the hot state to the cold state A method for manufacturing a multilayer structure using a method of manufacturing a hemispherical head-help structure by hot forming, characterized in that each of them is separated immediately after dismantling from the molding die (4, 5). According to claim 1, wherein the multi-layered structure using a method for manufacturing a hemispherical head help structure by the hot forming method, characterized in that it can be used as an insertion disc for adjusting the size of the head help structure to obtain any one of the plurality of disc (1) Manufacturing method.